Circulatory systems and blood vessels

Question 1

What’s the difference between single and double circulatory systems?

Answer 1

double systems pass the heart twice as there are two circuits. Also in a double system deoxygenated blood doesn’t mix with oxygenated blood.

Question 2

What’s the name of the body cavity in insects?

Answer 2

haemocoel

Question 3

What is insect blood called and what’s the difference between it and normal blood?

Answer 3

haemolymph and it only contains nutrients, waste and hormones (no oxygen)

Question 4

What is an open system?

Answer 4

one that has no vessels to contain the blood

Question 5

Why are open circulatory systems not efficient?

Answer 5

concentration gradients cannot be maintained and there is no control as to where it’s sent so if certain parts of the organism demand high levels then this probably cannot be met.

Question 6

What is a closed circulatory system?

Answer 6

one where the blood is enclosed in vessels and doesn’t directly come into contact with the cells of the body

Question 7

What is the benefit of a double circulatory system?

Answer 7

a relatively high blood pressure and fast flow can be maintained increasing the efficiency

Question 8

Describe the structure and function of arteries?

Answer 8

carry blood away from heart, generally oxygenated. Walls contain elastic fibres, collagen and smooth muscle. They have a narrow lumen

Question 9

Whats the main difference between arteries and arterioles?

Answer 9

blood is under much less pressure in arterioles so they have more smooth muscles so they can constrict or dilate.

Question 10

How are capillaries adapted to their role?

Answer 10

provides a large surface area, cross sectional area is greater than that of arterioles supplying them so blood flows slowly increasing time for gaseous exchange and walls are one cell thick = short diffusion distance

Question 11

How do veins overcome the problem of low blood pressure?

Answer 11

valves, skeletal muscle pump and respiratory muscle pump